(a) Field of the Invention
The present invention relates to an improved device of a micro mobile phone battery charger, and more particularly to a charger that is very compact to facilitate carrying, and that has a circuitry to enable the charger to automatically adapt to different voltages, and that is especially adapted for using car electricity and municipal electricity. In addition, the present invention is adapted for use with nickel hydrogen and lithium ion batteries, so that there is no need to discharge electricity prior to charging and there are no adverse memory effects.
(b) Description of the Prior Art
Mobile phones are very popular today. The mobile phone is used in conjunction with a charger so that it has sufficient power supply to enable it to be used at any time. However, conventional chargers are usually bulky and, due to various restrictions, has the following disadvantages:
1. As the conventional charger cannot adapt to different voltages, it cannot be used in countries where the voltage is different. PA0 2. As the conventional charger is equipped with a lead wire for recharging purposes, the wire may get entangled. It is also troublesome to assemble and connect the lead wire. PA0 3. The conventional charger can only charge nickel cadmium batteries and cannot effectively identify the types of batteries, which is impractical. PA0 4. As the conventional charger does not have a protection circuit, when the batteries are fully charged, it will not automatically turn off. PA0 5. Referring to Item 4 above, since the conventional charger does not include a protection circuit, when the batteries are fully charged, the temperature may rise, which will consume more power and may damage the internal components to shorten their useful life. PA0 6. The conventional charger is not provided with an electromagnetic interference filter circuit. Therefore, it cannot effectively avoid interference of electric currents and voltages. PA0 1. The greatest output current of the present charger is 250 mA. Charging is quick, and efficiency is high. The voltage can be adapted within the range of 90 to 250 V, and will not be restricted to any voltage environment. The present invention can be used in any country. PA0 2. The present invention can be used to charge nickel hydrogen or lithium ion batteries, which is an improvement over the prior art which can charge only a single type of battery. The present invention additionally has a delay identifying circuit and can identify nickel hydrogen or lithium ion batteries before proceeding with the charging process. PA0 3. The present invention is equipped with an over-charging protection circuit. When the battery is fully charged, the present invention will automatically turn off and charging will stop to protect the batteries. PA0 4. The present invention has an output protection circuit, so that there is no electricity leakage at the output end. PA0 5. The present invention is provided with an E.M.I. filter circuit, so that it can prevent interference due with electric currents and voltages used by household electrical appliances. PA0 6. As the power consumed by the present invention is only 40 mW, the temperature of the components will not rise, thus prolonging the service life of the present invention. PA0 7. The present invention can utilize municipal electricity and car electricity for recharging purposes, which is very practical compared to the prior art.